Last year while out shopping on a cold cold day all of a sudden our main key fob stopped working the starting and even unlocking, later at home we tried the second fob and it didn't work either, changed batteries and everything and nothing, at the same time noticed that the tire pressure was not working and didnt have any info to display and we tried numberous times to re learn and nothing came from it. It's getting cold and having remote start would be very helpful.
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Anyone have ​​​​an idea?

 

There's probably an issue with the Remote Control Door Lock Receiver. That part receives the signals from the TPMS sensors and the key fob. It could just be bad wiring/blown fuse or that part needs to be recalibrated or replaced.

If it were me, I would check for blown fuses first. If that checks good, I would disconnect/reconnect any plugs going to the remote control door lock receiver. I wouldn't be surprised at all if that fixed it.

The receiver is located in the cabin in front of and below the right rear window near the C-pillar. You will probably need to remove a couple panels to access it.

 

I had similar problems due to a low battery (cold remote starting in the -20C to -40C Canadian Winters = bad idea). As soon as I charged the battery back to full with a trickle charger, my Fob problems went away. It might be worth at least checking that ... if you can even borrow a trickle charger and let it run for a day, that might be all that's needed.

I also stopped remote starting my car in any temperature below -5C. I found out from a mechanic that the battery in my 07 doesn't start charging until the key is turned to the on position from inside the car. Kind of silly ... but it is what it is.

 

It sounds like there may be a problem with the car's electronic system, which is causing both key fobs to not work and the tire pressure monitoring system to malfunction. Changing the batteries didn't solve the issue, and attempting to re-learn the system didn't work either. As it's getting colder, having a remote start would be helpful, but it's unclear if this will be possible without addressing the underlying issue with the electronic system. It's recommended to bring the car to a trusted mechanic or dealership to diagnose and fix the problem.